OptRF long-term testing of reagent-free measurement

The wastewater treatment plant Peißenberg permitted WTW to perform long-term testing of the reagent-free measurement of COD and nitrate for a period of approx. 6 weeks. Two different WTW reagent-free measuring methods were tested: One was the IQ Sensor Net spectral sensor, the other was the new reagent-free photometry (OptRF) with the photoLab® 7600 UV-VIS. These two methods were compared to laboratory results from photometric cuvette tests.